JP2021150918A - Communication device and program - Google Patents

Abstract

To provide a mechanism capable of aligning communication timing among devices.SOLUTION: A communication device for performing radio communication with another communication device includes: a first radio communication part for communicating with complying with a first radio communication standard; a second radio communication part for communicating with complying with a second radio communication standard; and a control part for controlling the first radio communication part so as to transmit a first signal multiple times, the signal complying with the first radio communication standard and including setting information being information for setting communication timing of the second radio communication part.SELECTED DRAWING: Figure 1

Description

The present invention relates to communication devices and programs.

In recent years, various techniques for measuring the distance between devices (hereinafter, also referred to as distance measurement) have been developed. For example, Patent Document 1 below discloses a technique for measuring the distance between devices based on the time required from the transmission of a signal to the reception (hereinafter, also referred to as a propagation time).

U.S. Pat. No. 9,566,945

However, in the technique described in Patent Document 1, how to determine the timing of transmitting and receiving signals between devices has not been studied.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a mechanism capable of matching the timing of communication between devices.

In order to solve the above problems, according to a certain viewpoint of the present invention, the first communication device that performs wireless communication with another communication device and that performs communication conforming to the first wireless communication standard. The wireless communication unit, the second wireless communication unit that performs communication conforming to the second wireless communication standard, and the signal conforming to the first wireless communication standard, and the second wireless communication unit communicates. Provided is a communication device including a control unit that controls the first wireless communication unit so as to transmit a first signal, which is a signal including setting information which is information for setting a timing to be performed, a plurality of times. ..

Further, in order to solve the above problems, according to another viewpoint of the present invention, it is a communication device that performs wireless communication with another communication device, and performs communication conforming to the first wireless communication standard. A first wireless communication unit, a second wireless communication unit that performs communication conforming to the second wireless communication standard, and a signal conforming to the first wireless communication standard, the second wireless communication unit. When the first signal, which is a signal including setting information for setting the timing of communication, is received by the first wireless communication unit, the first signal is to perform communication at the timing set by the setting information. A communication device including a control unit that controls the wireless communication unit 2 is provided.

Further, in order to solve the above-mentioned problems, according to another viewpoint of the present invention, a first wireless communication unit that performs communication with another communication device in accordance with the first wireless communication standard, and the other. A computer that controls a communication device having a second wireless communication unit that performs communication with the communication device according to the second wireless communication standard is a signal conforming to the first wireless communication standard. A control unit that controls the first wireless communication unit so as to transmit a first signal, which is a signal including setting information which is information for setting a timing at which the second wireless communication unit performs communication, a plurality of times. A program is provided to make it function as.

Further, in order to solve the above-mentioned problems, according to another viewpoint of the present invention, a first wireless communication unit that performs communication with another communication device in accordance with the first wireless communication standard, and the other. A computer that controls a communication device having a second wireless communication unit that performs communication with the communication device according to the second wireless communication standard is a signal conforming to the first wireless communication standard. When the first signal, which is a signal including setting information for setting the timing for the second wireless communication unit to perform communication, is received by the first wireless communication unit, the timing set by the setting information. A program for functioning as a control unit that controls the second wireless communication unit so as to perform communication is provided.

As described above, according to the present invention, there is provided a mechanism capable of matching the timing of communication between devices.

It is a figure which shows an example of the structure of the system which concerns on one Embodiment of this invention. It is a sequence diagram which shows an example of the flow of the distance measurement processing executed by the system which concerns on this embodiment. It is a sequence diagram which shows an example of the flow of processing executed by the system which concerns on this embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. Configuration example>
FIG. 1 is a diagram showing an example of the configuration of the system 1 according to the embodiment of the present invention. As shown in FIG. 1, the system 1 according to the present embodiment includes a portable device 100 and a communication unit 200. The communication unit 200 in this embodiment is mounted on the vehicle 202. The vehicle 202 is an example of a user's usage target.

The present invention involves a communication device on the authenticated person side (also referred to as a first communication device) and a communication device on the certifier side (also referred to as a second communication device). The portable device 100 is an example of the first communication device. The communication unit 200 is an example of a second communication device.

In the system 1, when a user (for example, the driver of the vehicle 202) carries the portable device 100 and approaches the vehicle 202, wireless communication for authentication is performed between the portable device 100 and the communication unit 200. Then, if the authentication is successful, the door lock of the vehicle 202 is unlocked or the engine is started, and the vehicle 202 becomes available to the user. System 1 is also referred to as a smart entry system. Hereinafter, each component will be described in order.

(1) Portable device 100
The portable device 100 is a communication device that performs wireless communication with the communication unit 200. The portable device 100 is configured as an arbitrary device that is carried and used by a user. Examples of arbitrary devices include electronic keys, smartphones, wearable terminals, and the like. As shown in FIG. 1, the portable device 100 includes a first wireless communication unit 110, a second wireless communication unit 120, a storage unit 130, and a control unit 140.

The first wireless communication unit 110 has a function of performing communication conforming to the first wireless communication standard. For example, the first wireless communication unit 110 performs wireless communication with the communication unit 200. The second wireless communication unit 120 has a function of performing communication conforming to the second wireless communication standard. For example, the second wireless communication unit 120 performs wireless communication with the communication unit 200.

As an example of the first wireless communication standard, BLE (Bluetooth Low Energy (registered trademark)) can be mentioned. BLE is known as a low power consumption wireless communication standard. In BLE, signals in the 2.4 GHz band are transmitted and received.

As an example of the second wireless communication standard, there is one that transmits / receives a signal using a UWB (Ultra-Wide Band). In wireless communication of signals using UWB, if the impulse method is used, the propagation time of radio waves can be measured with high accuracy by using radio waves with a very short pulse width of nanoseconds or less, and the propagation time can be increased. Based on distance measurement can be performed with high accuracy. UWB often refers to a frequency band of about 3 GHz to about 10 GHz.

As described above, the second wireless communication standard may be a wireless communication standard using a carrier wave having a frequency higher than the frequency of the carrier wave in the first wireless communication standard. In the following, it is assumed that the first wireless communication standard is BLE. That is, the first wireless communication unit 110 is configured as a communication interface capable of communicating with BLE. Further, it is assumed that the second wireless communication standard is a wireless communication standard using UWB. That is, the second wireless communication unit 120 is configured as a communication interface capable of UWB communication.

The storage unit 130 has a function of storing various information for the operation of the portable device 100. For example, the storage unit 130 stores a program for operating the portable device 100, an ID (identifier) for authentication, a password, an authentication algorithm, and the like. The storage unit 130 is composed of, for example, a storage medium such as a flash memory and a processing device that executes recording / reproduction on the storage medium.

The control unit 140 has a function of executing processing in the portable device 100. For example, the control unit 140 controls the first wireless communication unit 110 and the second wireless communication unit 120 to communicate with the communication unit 200. Further, the control unit 140 reads the information from the storage unit 130 and writes the information to the storage unit 130. Further, the control unit 140 controls the authentication process performed with the communication unit 200. The control unit 140 is composed of, for example, an electronic circuit such as a CPU (Central Processing Unit) and a microprocessor.

(2) Communication unit 200
The communication unit 200 is a communication device that performs wireless communication with the portable device 100. The communication unit 200 is provided in association with the vehicle 202. Here, it is assumed that the communication unit 200 is mounted on the vehicle 202, such as the communication unit 200 being installed in the vehicle interior of the vehicle 202 or being incorporated in the vehicle 202 as a communication module. As shown in FIG. 1, the communication unit 200 includes a first wireless communication unit 210, a second wireless communication unit 220, a storage unit 230, and a control unit 240.

The first wireless communication unit 210 has a function of performing communication conforming to the first wireless communication standard. For example, the first wireless communication unit 210 performs wireless communication with the portable device 100. In the following, it is assumed that the first wireless communication unit 210 is configured as a communication interface capable of communicating with BLE.

The second wireless communication unit 220 has a function of performing communication conforming to the second wireless communication standard. For example, the second wireless communication unit 220 performs wireless communication with the portable device 100. In the following, it is assumed that the second wireless communication unit 220 is configured as a communication interface capable of communicating in UWB.

The storage unit 230 has a function of storing various information for the operation of the communication unit 200. For example, the storage unit 230 stores a program for operating the communication unit 200, an authentication algorithm, and the like. The storage unit 230 includes, for example, a storage medium such as a flash memory, and a processing device that executes recording / reproduction on the storage medium.

The control unit 240 has a function of controlling the overall operation of the in-vehicle device mounted on the communication unit 200 and the vehicle 202. As an example, the control unit 240 controls the first wireless communication unit 210 and the second wireless communication unit 220 to communicate with the portable device 100. Further, the control unit 240 reads the information from the storage unit 230 and writes the information to the storage unit 230. The control unit 240 also functions as an authentication control unit that controls the authentication process performed with the portable device 100. The control unit 240 also functions as a door lock control unit that controls the door lock of the vehicle 202, and locks and unlocks the door lock. The control unit 240 also functions as an engine control unit that controls the engine of the vehicle 202, and starts / stops the engine. The power source provided in the vehicle 202 may be a motor or the like in addition to the engine. The control unit 240 is configured as, for example, an ECU (Electronic Control Unit).

<2. Technical features>
(1) Distance measurement processing The portable device 100 and the communication unit 200 perform distance measurement processing. The distance measuring process is a process of measuring the distance between the portable device 100 and the communication unit 200. The distance measured in the distance measurement process is also referred to as a distance measurement value below.

In the distance measurement process, signals can be transmitted and received wirelessly.

An example of a signal transmitted / received in the distance measuring process is a distance measuring signal. The distance measuring signal is a signal transmitted and received to measure the distance between the devices. The distance measuring signal is also a signal to be measured. For example, the time required to send and receive the distance measurement signal is measured. Typically, the ranging signal is configured in a frame format that does not have a payload portion to store the data. Of course, the distance measuring signal may be configured in a frame format having a payload portion for storing data.

In the distance measuring process, a plurality of distance measuring signals can be transmitted and received between the devices. Of the plurality of distance measuring signals, the distance measuring signal transmitted from one device to the other device is also referred to as a first distance measuring signal. Then, the distance measuring signal transmitted from the device that received the first distance measuring signal to the device that transmitted the first distance measuring signal is also referred to as a second distance measuring signal.

Another example of a signal transmitted and received in the distance measuring process is a data signal. A data signal is a signal that stores and conveys data. The data signal is composed of a frame format having a payload portion for storing data.

Sending and receiving signals in distance measurement processing is also referred to as distance measurement communication below. In the present embodiment, it is assumed that the second wireless communication unit 120 and the second wireless communication unit 220 perform distance measurement communication. In the distance measuring process, the distance between the second wireless communication unit 120 and the second wireless communication unit 220 that performed the distance measuring communication is measured as the distance between the portable device 100 and the communication unit 200. NS.

An example of the distance measuring process will be described with reference to FIG.

FIG. 2 is a sequence diagram showing an example of the flow of distance measurement processing executed by the system 1 according to the present embodiment. As shown in FIG. 2, the portable device 100 and the communication unit 200 are involved in this sequence.

As shown in FIG. 2, first, the second wireless communication unit 120 of the portable device 100 transmits the first ranging signal (step S12). For example, the first ranging signal may be transmitted as a signal using UWB.

Next, when the second wireless communication unit 220 of the communication unit 200 receives the first ranging signal from the portable device 100, the second wireless communication unit 220 transmits a second ranging signal as a response to the first ranging signal. (Step S14). For example, the second ranging signal may be transmitted as a signal using UWB.

At this time, the control unit 240 of the communication unit 200 measures the time ΔT2 from the reception time of the first distance measurement signal to the transmission time of the second distance measurement signal in the communication unit 200. On the other hand, when the control unit 140 of the portable device 100 receives the second ranging signal from the communication unit 200, the control unit 140 receives the second ranging signal from the transmission time of the first ranging signal in the portable device 100. The time ΔT1 until the time is measured.

Next, the second wireless communication unit 220 of the portable device 100 transmits a data signal including information indicating the time ΔT1 (step S16). For example, the data signal may be transmitted as a signal using UWB.

Then, when the control unit 240 of the communication unit 200 receives the data signal, the control unit 240 determines the distance between the portable device 100 and the communication unit 200 based on the ΔT1 indicated by the information contained in the data signal and the measured time ΔT2. Calculate (step S18). Specifically, the control unit 240 calculates the one-way signal propagation time by dividing the result of ΔT1-ΔT2 by 2. Then, the control unit 240 calculates the distance (that is, the distance measurement value) between the portable device 100 and the communication unit 200 by multiplying the propagation time by the speed of the signal.

The distance measurement value can be used for authentication of the portable device 100. For example, the control unit 240 determines the authentication success when the distance measurement value is less than a predetermined threshold value. On the other hand, the control unit 240 determines the authentication failure when the distance measurement value is equal to or higher than a predetermined threshold value.

(2) Communication Timing Control-Operation of Portable Device 100 The control unit 140 is a signal conforming to the first wireless communication standard, and is information for setting the timing at which the second wireless communication unit 120 communicates. The first wireless communication unit 110 is controlled so that the first signal, which is a signal including the setting information, is transmitted a plurality of times. For example, the portable device 100 transmits a BLE signal including setting information for setting a timing for performing communication using UWB a plurality of times. By transmitting the setting information, it is possible to match the timing of performing communication conforming to the second wireless communication standard with the communication unit 200 that has received the setting information. Further, by transmitting the first signal a plurality of times, it is possible to improve the probability that the communication unit 200 succeeds in receiving the first signal.

The control unit 140 controls the second wireless communication unit 120 so as to perform communication at the timing set by the setting information. For example, the portable device 100 performs communication using the UWB with the communication unit 200 at a timing set in the setting information transmitted including the BLE signal. With such a configuration, communication conforming to the second wireless communication standard can be performed with the communication unit 200 at an appropriate timing. An example of communication conforming to the second wireless communication standard is distance measurement communication.

The control unit 140 controls the second wireless communication unit 120 so as to perform communication at the timing set by the setting information, and determines the second signal, which is a signal conforming to the second wireless communication standard, by the setting information. The second wireless communication unit 120 may be controlled so as to transmit at a set timing. For example, for example, the portable device 100 transmits a signal using UWB at a timing set in the setting information transmitted including the BLE signal. With such a configuration, the communication unit 200 that has received the setting information can transmit the second signal at the timing when the second signal can be received. When the communication conforming to the second wireless communication standard is distance measurement communication, an example of the second signal is a distance measurement signal.

− Operation of the communication unit 200 When the first signal is received by the first wireless communication unit 210, the operation control unit 240 controls the second wireless communication unit 220 so as to perform communication at the timing set by the setting information. do.
For example, when the communication unit 200 receives a BLE signal including setting information for setting a timing for performing communication using UWB, the communication unit 200 performs communication using UWB at the timing set in the setting information. Do with 100. With such a configuration, communication conforming to the second wireless communication standard can be performed with the portable device 100 at an appropriate timing.

Here, the communication unit 200 may receive the first signal a plurality of times. When a plurality of first signals are received, the control unit 240 communicates with the second wireless communication unit at a timing set by the setting information included in at least one of the plurality of first signals. Control 220.

The control unit 240 controls the second wireless communication unit 220 so as to perform communication at the timing set by the setting information, and performs a process for receiving the second signal at the timing set by the setting information. The second wireless communication unit 220 may be started from the corresponding timing. For example, the communication unit 200 starts a process for receiving a signal using UWB from a timing corresponding to a timing set in the setting information included in the received BLE signal. In other words, the control unit 240 does not start the process for receiving the second signal until the timing corresponding to the timing set by the setting information. With such a configuration, it is possible to shorten the period for executing the process for receiving the second signal in the communication unit 200.

An example of the timing according to the timing set by the setting information is the same timing as the timing set by the setting information. According to such a configuration, the communication unit 200 starts the process for receiving the second signal at the timing of receiving the second signal. Therefore, in the communication unit 200, it is possible to minimize the period for executing the process for receiving the second signal.

Another example of the timing according to the timing set by the setting information is the timing before a predetermined time from the timing set by the setting information. According to such a configuration, the communication unit 200 starts the process for receiving the second signal from a predetermined time before the timing of receiving the second signal. With such a configuration, the communication unit 200 can start the process for receiving the second signal with a margin at least before the arrival of the second signal. Therefore, even if the timing at which the first signal arrives is delayed due to the influence of interference or the like, or the process of acquiring the setting information from the received first signal takes a long time, the communication unit 200 has the first signal. It is possible to reliably receive the signal of 2.

An example of processing for receiving the second signal is waiting for reception.

Waiting for reception refers to a state in which a desired signal can be acquired and processed. The state in which the signal can be acquired and processed may be the start of capturing the signal received through the antenna into the processing device. Further, the state in which the signal can be acquired and processed may be the start of execution of various subsequent processes for the signal captured in the processing device. The state in which the signal can be acquired and processed means that the signal is taken into the processing device so as to be executed when it is detected that the desired signal is received through the antenna. May receive the desired signal through the antenna.

Examples of the subsequent various processes include a process of determining whether or not the signal received via the antenna is a desired signal, a process of confirming information contained in the signal, and the like.

The state of waiting for reception is also referred to as the state of waiting for reception. The period in the reception waiting state is also referred to as the reception waiting period.

According to the present embodiment, the period in which the communication unit 200 is in the reception waiting state for receiving the second signal is shortened, so that the power consumption of the communication unit 200 can be suppressed.

-Setting information Each of the first signals transmitted multiple times includes the time length from the time when the first signal is transmitted to the time when communication conforms to the second wireless communication standard is performed as setting information. You may be. In other words, the setting information may include a time length from the time when the portable device 100 transmits the first signal including the setting information to the time when the communication conforming to the second wireless communication standard is performed. According to such a configuration, the communication unit 200 can know the timing of performing communication conforming to the second wireless communication standard based on the time when the first signal is received and the time length included in the setting information. It will be possible.

Alternatively, each of the first signals transmitted a plurality of times sets information corresponding to the time length from the time when the first signal is transmitted to the time when the communication conforms to the second wireless communication standard is performed. Each may be included as information. In other words, the setting information includes information corresponding to the time length from the time when the portable device 100 transmits the first signal including the setting information to the time when the communication conforming to the second wireless communication standard is performed. May be good. According to such a configuration, the communication unit 200 performs communication conforming to the second wireless communication standard based on the time when the first signal is received and the time length corresponding to the information included in the setting information. It becomes possible to know.

The correspondence relationship between the time length and the information corresponding to the time length is shared between the portable device 100 and the communication unit 200. An example of such a correspondence is shown in Table 1 below.

In Table 1 above, the alphabet is given as an example of the information corresponding to the time length, but other information such as numbers may be used.

As described above, the portable device 100 can transmit the second signal at the timing set by the setting information. In that case, each of the first signals transmitted a plurality of times may include, as setting information, the time length from the time when the first signal is transmitted to the time when the second signal is transmitted. .. In other words, the setting information may include the time length from the time when the portable device 100 transmits the first signal including the setting information to the time when the second signal is transmitted. According to such a configuration, the communication unit 200 can know the timing at which the portable device 100 transmits the second signal based on the time when the first signal is received and the time length included in the setting information. It becomes.

Alternatively, each of the first signals transmitted a plurality of times includes information corresponding to the time length from the time when the first signal is transmitted to the time when the second signal is transmitted as setting information. You may. In other words, the setting information may include information corresponding to the time length from the time when the portable device 100 transmits the first signal including the setting information to the time when the second signal is transmitted. According to such a configuration, the communication unit 200 determines the timing at which the portable device 100 transmits the second signal based on the time when the first signal is received and the time length corresponding to the information included in the setting information. It becomes possible to know.

The example of the information included in the setting information has been described above. In any example, the communication unit 200 can know when the portable device 100 transmits the second signal. Therefore, the communication unit 200 can start the process for receiving the second signal at the timing when the portable device 100 transmits the second signal.

In BLE, the connection is maintained by repeatedly transmitting and receiving signals at a predetermined cycle from the establishment of the connection to the end of the connection. The transmission and reception of signals performed in such a predetermined cycle is also referred to as periodic communication below. In BLE, periodic communication is performed while hopping 37 channels. Therefore, in BLE, it is possible to maintain the connection even when one periodic communication fails. Note that hopping is to change the channel. Further, the failure of periodic communication means that the receiving side fails to receive the signal.

In periodic communication, empty packets (Empty Packets) are transmitted and received when there is no information to be transmitted and received. An empty packet is a packet in which no data is stored in the payload portion that stores the data.

When the first wireless communication standard is BLE, the first signal including the setting information may be transmitted in the periodic communication. That is, in the present embodiment, in the periodic communication, the first signal including the setting information may be transmitted and received instead of the empty packet.

(3) Process Flow FIG. 3 is a sequence diagram showing an example of a process flow executed by the system 1 according to the present embodiment. As shown in FIG. 3, the portable device 100 and the communication unit 200 are involved in this sequence.

As shown in FIG. 3, first, the control unit 140 of the mobile device 100 to transmit a first signal including setting information indicating sending a second signal after T _A seconds, the first wireless communication The unit 110 is controlled (step S102). The first signal may be transmitted as a BLE signal.

When the first signal is received by the first wireless communication unit 210, the control unit 240 of the communication unit 200 controls the first wireless communication unit 210 so as to transmit a response to the first signal (step). S104). The response to the first signal may be a signal including information indicating that the reception of the first signal has been successful. Control unit 240, by acquiring the setting information included in the first signal received in step S102, it is possible to recognize that the first signal is transmitted from the mobile device 100 after T _A seconds. The response corresponding to the first signal may be transmitted as a BLE signal.

Next, the control unit 140 of the mobile device 100 to transmit a first signal including setting information indicating sending a second signal after T _B seconds, which controls the first wireless communication unit 110 (step S106). The first signal may be transmitted as a BLE signal.

When the first signal is received by the first wireless communication unit 210, the control unit 240 of the communication unit 200 controls the first wireless communication unit 210 so as to transmit a response to the first signal (step). S108). Control unit 240, by acquiring the setting information included in the first signal received in step S106, it is possible to recognize that the first signal is transmitted from the mobile device 100 after T _B seconds. The response corresponding to the first signal may be transmitted as a BLE signal.

Next, the control unit 140 of the portable device 100 controls the first wireless communication unit 110 so as to transmit the first signal including the setting information indicating that the second signal is transmitted after _{TC seconds (} Step S110). The first signal may be transmitted as a BLE signal.

When the first signal is received by the first wireless communication unit 210, the control unit 240 of the communication unit 200 controls the first wireless communication unit 210 so as to transmit a response to the first signal (step). S112). By acquiring the setting information included in the first signal received in step S110, the control unit 240 can recognize that the first signal is transmitted from the portable device 100 after _{TC seconds.} The response corresponding to the first signal may be transmitted as a BLE signal.

Next, the control unit 140 of the portable device 100 controls the first wireless communication unit 110 so as to transmit the first signal including the setting information indicating that the second signal is transmitted after _{TD seconds (step).} S114). The first signal may be transmitted as a BLE signal.

When the first signal is received by the first wireless communication unit 210, the control unit 240 of the communication unit 200 controls the first wireless communication unit 210 so as to transmit a response to the first signal (step). S116). By acquiring the setting information included in the first signal received in step S114, the control unit 240 can recognize that the first signal is transmitted from the portable device 100 after _{TD seconds.} The response corresponding to the first signal may be transmitted as a BLE signal.

Next, the control unit 140 of the portable device 100 controls the first wireless communication unit 110 so as to transmit the first signal including the setting information indicating that the second signal is transmitted after _{TE seconds (} Step S118). The first signal may be transmitted as a BLE signal.

When the first signal is received by the first wireless communication unit 210, the control unit 240 of the communication unit 200 controls the first wireless communication unit 210 so as to transmit a response to the first signal (step). S120). By acquiring the setting information included in the first signal received in step S118, the control unit 240 can recognize that the first signal is transmitted from the portable device 100 after _{TE seconds.} The response corresponding to the first signal may be transmitted as a BLE signal.

Then, the control unit 240 of the communication unit 200 sets the second wireless communication unit 220 so as to start the reception waiting from the timing corresponding to the timing set in the setting information included in the first signal transmitted a plurality of times. Control (step S122). For example, the communication unit 200 starts waiting for reception of a signal using UWB.

As an example, the timing of the communication unit 200 starts waiting is T _A seconds after the timing of receiving the first signal at step S102. As another example, the timing of the communication unit 200 starts waiting is T _B seconds after the timing of receiving the first signal at step S106. As another example, the timing at which the communication unit 200 starts waiting for reception is _TC seconds after the timing at which the first signal is received in step S110. As another example, the timing of the communication unit 200 starts waiting is T _D seconds after the timing of receiving the first signal at step S114. As another example, the timing of the communication unit 200 starts waiting is a T _E seconds after the timing of receiving the first signal at step S118.

On the other hand, the control unit 140 of the portable device 100 transmits the first ranging signal as the second signal at the timing set in the setting information included in the first signal transmitted a plurality of times. The wireless communication unit 120 is controlled (step S124). For example, the first ranging signal may be transmitted as a signal using UWB.

As an example, the timing at which the portable device 100 transmits a first ranging signal as the second signal is the T _A seconds after the timing of transmitting a first signal at step S102. As another example, the timing at which the portable device 100 transmits a first ranging signal as the second signal is the T _B seconds after the timing of transmitting a first signal at step S106. As another example, the timing at which the portable device 100 transmits the first ranging signal as the second signal is _TC seconds after the timing at which the first signal is transmitted in step S110. As another example, the timing at which the portable device 100 transmits a first ranging signal as the second signal is T _D seconds after the timing of transmitting the first signal at step S114. As another example, the timing at which the portable device 100 transmits a first ranging signal as the second signal is the T _E seconds after the timing of transmitting the first signal at step S118.

Next, when the second wireless communication unit 120 of the portable device 100 receives the first distance measurement signal from the communication unit 200, the second distance measurement signal is transmitted as a response to the first distance measurement signal. (Step S126). For example, the second ranging signal may be transmitted as a signal using UWB.

At this time, the control unit 240 of the communication unit 200 measures the time ΔT2 from the reception time of the first distance measurement signal to the transmission time of the second distance measurement signal in the communication unit 200. On the other hand, when the control unit 140 of the portable device 100 receives the second ranging signal from the communication unit 200, the control unit 140 receives the second ranging signal from the transmission time of the first ranging signal in the portable device 100. The time ΔT1 until the time is measured.

Next, the second wireless communication unit 220 of the portable device 100 transmits a data signal including information indicating the time ΔT1 (step S128). For example, the data signal may be transmitted as a signal using UWB.

Then, when the control unit 240 of the communication unit 200 receives the data signal, the control unit 240 determines the distance between the portable device 100 and the communication unit 200 based on the ΔT1 indicated by the information contained in the data signal and the measured time ΔT2. Calculate (step S130). Specifically, the control unit 240 calculates the one-way signal propagation time by dividing the result of ΔT1-ΔT2 by 2. Then, the control unit 240 calculates the distance (that is, the distance measurement value) between the portable device 100 and the communication unit 200 by multiplying the propagation time by the speed of the signal.

After that, the control unit 240 of the communication unit 200 controls the second wireless communication unit 220 so as to stop waiting for reception (step S132). As an example, the control unit 240 may stop the reception wait after a predetermined time from the start of the reception wait. As another example, the control unit 240 may stop waiting for reception when the data signal is received in step S130. As another example, the control unit 240 may stop the reception wait when the distance measurement value is calculated. In any case, it is possible to suppress the power consumption by stopping the reception waiting.

The processes related to steps S102 to S132 may be repeatedly executed.

Further, in the above, an example is shown in which all the signals transmitted / received in steps S102, S106, S110, S114, and S118 are the first signals including the setting information, but the present invention is not limited to such an example. At least a part of the signals transmitted and received in steps S102, S106, S110, S114, and S118 may not include the setting information. For example, at least a part of the signals transmitted and received in steps S102, S106, S110, S114, and S118 may be empty packets of BLE.

<3. Supplement>
Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

For example, in the above embodiment, an example in which the device for transmitting the first signal including the setting information and the device for transmitting the second signal are the same has been described, but the present invention is not limited to such an example. For example, the device that transmits the first signal including the setting information and the device that transmits the second signal may be different. Specifically, when the portable device 100 transmits the first signal including the setting information a plurality of times, the communication unit 200 transmits the second signal at the timing set in the setting information included in the first signal. You may. In that case, each of the first signals transmitted a plurality of times is the time from the second signal time when the portable device 100 transmits the first signal to the time when the communication unit 200 transmits the second signal. Contains information corresponding to the length or the time length. On the other hand, the portable device 100 starts the process for receiving the second signal from the timing corresponding to the timing set in the setting information.

For example, in the above description, the communication device for transmitting the setting information is the portable device 100, and the communication device for receiving the setting information is the communication unit 200, but the present invention is not limited to such an example. For example, the communication device that transmits the setting information may be the communication unit 200, and the communication device that receives the setting information may be the portable device 100. That is, one of the communication device that transmits the setting information and the communication device that receives the setting information may be the communication unit 200. Then, the other one of the communication device for transmitting the setting information and the communication device for receiving the setting information may be the portable device 100.

For example, in the above embodiment, it has been described that the data signal includes information indicating the time ΔT1 from the transmission time of the first distance measurement signal to the reception time of the second distance measurement signal in the portable device 100. , The present invention is not limited to such examples. The data signal may include information regarding the transmission time of the first ranging signal and the reception time of the second ranging signal. Hereinafter, another example of the information contained in the data signal will be described.

Another example of the information included in the data signal is information indicating the transmission time of the first distance measurement signal and the reception time of the second distance measurement signal in the portable device 100. That is, the portable device 100 may transmit the start and end time stamps of ΔT1 without calculating ΔT1.

Another example of the information contained in the data signal is that the portable device 100 and the communication unit 200 are calculated based on the time from the transmission time of the first distance measurement signal to the reception time of the second distance measurement signal. Information indicating the distance between them. That is, the portable device 100 may calculate the distance between the portable device 100 and the communication unit 200, and transmit information indicating the calculated distance to the communication unit 200. For example, when ΔT2 is a fixed value, the portable device 100 can calculate the distance measurement value by measuring ΔT1.

Another example of the information contained in the data signal is information indicating the result of authentication between the portable device 100 and the communication unit 200 based on the distance between the portable device 100 and the communication unit 200. As an example, authentication can be performed based on whether or not the distance between the portable device 100 and the communication unit 200 is equal to or less than a predetermined threshold value.

For example, in the above embodiment, the example in which the portable device 100 transmits the first distance measuring signal has been described, but the present invention is not limited to such an example. For example, the communication unit 200 may transmit the first ranging signal. In that case, when the portable device 100 receives the first ranging signal, it transmits a second ranging signal as a response. Then, the portable device 100 transmits a data signal including information indicating the time ΔT2 from the reception time of the first ranging signal to the transmission time of the second ranging signal. On the other hand, the communication unit 200 determines the distance measurement value based on the time ΔT1 from the transmission time of the first distance measurement signal to the reception time of the second distance measurement signal and the time ΔT2 included in the data signal. calculate.

For example, in the above embodiment, an example of calculating the distance measurement value based on the propagation time has been described, but the present invention is not limited to such an example. For example, the distance measurement value may be calculated based on the radio field intensity.

For example, in the above embodiment, an example in which communication conforming to the second wireless communication standard is distance measurement communication has been described, but the present invention is not limited to such an example. Communication conforming to the second wireless communication standard may be performed for any purpose.

For example, in the above embodiment, the example in which the first wireless communication standard is BLE and the second wireless communication standard uses UWB has been described, but the present invention is not limited to such an example. As an example, in the first radio communication standard, a signal in the ultra high frequency (UHF) band and a signal in the long wave (LF: low frequency) band may be used. For example, a UHF band signal may be used for transmission from the portable device 100 to the communication unit 200, and an LF band signal may be used for transmission from the communication unit 200 to the mobile device 100. As another example, as the first wireless communication standard or the second wireless communication standard, Wi-Fi (registered trademark), one using infrared rays, NFC (Near Field Communication) and the like may be used.

For example, in the above embodiment, an example in which the communication unit 200 is a communication device mounted on a vehicle has been described, but the present invention is not limited to such an example. The communication unit 200 may be mounted on an arbitrary moving body such as an aircraft and a ship other than a vehicle. Here, the moving body is a moving device.

For example, in the above embodiment, an example in which the present invention is applied to a smart entry system has been described, but the present invention is not limited to such an example. The present invention is applicable to any system that performs communication conforming to a plurality of wireless communication standards. For example, the present invention is applicable to a pair including any two devices such as a portable device, a vehicle, a smartphone, a drone, a house, and a home electric appliance. It should be noted that the pair may include two devices of the same type or two different types of devices.

The series of processes by each device described in the present specification may be realized by using software, hardware, or a combination of software and hardware. The programs constituting the software are stored in advance in, for example, a recording medium (non-transitory media) provided inside or outside each device. Then, each program is read into RAM at the time of execution by a computer and executed by a processor such as a CPU. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, or the like. Further, the above-mentioned computer program may be distributed via, for example, a network without using a recording medium.

Further, the processes described with reference to the flowchart and the sequence diagram in the present specification do not necessarily have to be executed in the order shown in the drawings. Some processing steps may be performed in parallel. Further, additional processing steps may be adopted, and some processing steps may be omitted.

1: System, 100: Portable device, 110: First wireless communication unit, 120: Second wireless communication unit, 130: Storage unit, 140: Control unit, 200: Communication unit, 202: Vehicle, 210: First Wireless communication unit, 220: second wireless communication unit, 230: storage unit, 240: control unit

Claims (12)

A communication device that performs wireless communication with other communication devices.
With the first wireless communication unit that performs communication conforming to the first wireless communication standard,
With the second wireless communication unit that performs communication conforming to the second wireless communication standard,
The first signal, which is a signal conforming to the first wireless communication standard and includes setting information which is information for setting the timing at which the second wireless communication unit performs communication, is transmitted a plurality of times. A control unit that controls the first wireless communication unit to transmit, and a control unit.
A communication device equipped with. The communication device according to claim 1, wherein the control unit controls the second wireless communication unit so as to perform communication at a timing set by the setting information. Each of the first signals transmitted a plurality of times includes, as the setting information, the time length from the time when the first signal is transmitted to the time when communication conforms to the second wireless communication standard is performed. , The communication device according to claim 1 or 2. Each of the first signals transmitted a plurality of times sets information corresponding to the time length from the time when the first signal is transmitted to the time when communication conforms to the second wireless communication standard is performed. The communication device according to claim 1 or 2, which is included as information, respectively. The control unit controls the second wireless communication unit so as to perform communication at the timing set by the setting information, and obtains the second signal, which is a signal conforming to the second wireless communication standard. The communication device according to claim 1 or 2, which controls the second wireless communication unit so as to transmit at a timing set by the setting information. According to claim 5, each of the first signals transmitted a plurality of times includes, as the setting information, the time length from the time when the first signal is transmitted to the time when the second signal is transmitted. The communication device described. Each of the first signals transmitted a plurality of times includes information corresponding to the time length from the time when the first signal is transmitted to the time when the second signal is transmitted as the setting information. The communication device according to claim 5. One of the communication device and the other communication device is mounted on the vehicle.
The communication device according to any one of claims 1 to 7, wherein the communication device and the other one of the other communication devices are devices carried by the user of the vehicle. A communication device that performs wireless communication with other communication devices.
With the first wireless communication unit that performs communication conforming to the first wireless communication standard,
With the second wireless communication unit that performs communication conforming to the second wireless communication standard,
The first signal, which is a signal conforming to the first wireless communication standard and includes setting information for setting the timing at which the second wireless communication unit performs communication, is the first wireless communication. When received by the unit, the control unit that controls the second wireless communication unit to perform communication at the timing set by the setting information, and the control unit.
A communication device equipped with. The control unit receives the second signal, which is a signal conforming to the second wireless communication standard, by controlling the second wireless communication unit so as to perform communication at the timing set by the setting information. The communication device according to claim 9, wherein the second wireless communication unit starts the process for performing the process from the timing corresponding to the timing set by the setting information. A first wireless communication unit that communicates with other communication devices in accordance with the first wireless communication standard, and a first wireless communication unit that performs communication in compliance with the second wireless communication standard with the other communication devices. A computer that controls a communication device having two wireless communication units,
The first signal, which is a signal conforming to the first wireless communication standard and includes setting information which is information for setting the timing at which the second wireless communication unit performs communication, is transmitted a plurality of times. A control unit that controls the first wireless communication unit to transmit,
A program to function as. A first wireless communication unit that communicates with other communication devices in accordance with the first wireless communication standard, and a first wireless communication unit that performs communication in compliance with the second wireless communication standard with the other communication devices. A computer that controls a communication device having two wireless communication units,
The first signal, which is a signal conforming to the first wireless communication standard and includes setting information for setting the timing at which the second wireless communication unit performs communication, is the first wireless communication. A control unit that controls the second wireless communication unit to perform communication at a timing set by the setting information when received by the unit.
A program to function as.

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